1. Field of the Invention
This patent relates to the feeding of persons with gastric feeding tubes, and more particularly to gravity bolus feeding devices for use in the feeding of such persons.
2. Summary of Related Art
For persons with gastric feeding tubes, there are three common methods for feeding:                1. Gravity feeding with an intravenous-type bag and tubing;        2. Utilizing a feeding pump with bag and tubing; and        3. Gravity bolus feeding.The first two methods are commonly used in the hospital setting. For many persons with gastric feeding tubes, it is important to be able to vent air and stomach contents back up the gastric tube during and after a feeding. Methods 1 and 2 above can benefit from the device described in U.S. Pat. No. 6,482,170.        
Gravity bolus feeding is the primary method for out-of-hospital feeding. Typically, gravity bolus feeding uses a syringe barrel connected to the gastric feeding tube. The syringe barrel is filled with liquid food. To control the rate of feeding, the syringe barrel is raised or lowered by hand. The open tube allows air and stomach contents to vent back into the syringe barrel.
This method suffers from a number of disadvantages:                (a) A person must hold the syringe barrel for the entire twenty to forty minutes a typical feeding takes.        (b) Holding the syringe barrel too high results in too rapid of a feeding, which can cause reflux of the stomach contents and possible aspiration.        (c) Holding the syringe barrel too low causes the liquid food to return to the syringe barrel, which increases feeding time.        (d) Once the feeding is started, it is difficult to interrupt or stop if necessary.        (e) When venting occurs, the contents of the syringe barrel are often splashed out of the open top.        (f) The typical syringe barrel only holds 60 cubic centimeters of liquid food, much less than the average of approximately 200 cubic centimeters that many adults require for a feeding.        (g) The flow of liquid food can only be stopped by clamping the gastric feeding tube, which also prevents venting back into the syringe barrel.        